I've had four recently. All but one were due to excessive house pressure. First one had no pressure regulator to the house, his pressure was 105 psi. The customer couldn't understand why it worked before now without a regulator. They are doing some major work in his city, new water mains means more pressure. Second one was 150 psi, bad pressure regulator. The regulator had swivel fittings, I was able to replace it without soldering. Third one, house pressure was 65psi, a new inlet valve fixed it. The fourth one was at 100 psi. The installation manual says 100 psi is acceptable, not true, a new inlet valve did not fix it. Her pressure regulator was connected to pex, I referred a plumber.